Results for “command substitution”
Small, practical examples. Search by task or narrow things down below.
Check whether a file is already sorted
Linux Commands: Use sort -C for a quiet status check that does not rewrite the file.
Linux Commands✓ Tested
Check whether two practice files match
Linux Commands: Check whether two practice files match using GNU/Linux commands in an empty practice directory.
Linux Commands✓ Tested
Collapse repeated spaces
Linux Commands: Use tr -s when repeated occurrences of a character should become one.
Linux Commands✓ Tested
Collect a serial line in a fixed buffer
Read a short command without dynamic String allocation.
serial line✓ Tested
Compress a stream to a chosen filename
Linux Commands: Use gzip -c to leave the source file untouched and choose the destination explicitly.
Linux Commands✓ Tested
Convert a Unix timestamp to UTC
Linux Commands: Use the @ syntax with GNU date for seconds since the Unix epoch.
Linux Commands✓ Tested
Convert tab stops to spaces
Linux Commands: Use expand with a fixed tab width when preparing plain-text alignment.
Linux Commands✓ Tested
Copy a directory while preserving attributes
Linux Commands: Use cp -a for a recursive local copy that preserves links and ordinary file attributes.
Linux Commands✓ Tested
Copy a file with explicit permissions
Linux Commands: Use install to create parent directories and set the destination mode in one operation.
Linux Commands✓ Tested
Count bytes in a file
Linux Commands: Use wc -c for byte length rather than Unicode character count.
Linux Commands✓ Tested
Count matching lines
Linux Commands: Use grep -c to count matching lines rather than individual occurrences.
Linux Commands✓ Tested
Count newline-terminated records
Linux Commands: Count newline-terminated records using GNU/Linux commands in an empty practice directory.
Linux Commands✓ Tested